Раскройте скобки, употребляя глаголы в Past Simpl или Past Continuous

1.They were drinking tea when I came home2.He was walking along the river when a boat passed3.The old man was thinking about his plan when he falled a sleep4.We listened to an intereting lecture yesterday5. When I was entering the classrom,the teacher was wrote words on the black board and the pupils were copying ...